Preview at WWDC likely in June, followed by September launch.
iPad Air 2 Rumored to Launch in October, Updated Retina iPad Mini May Come Later
Commercial Times also suggests that the next-generation Retina iPad mini might not launch alongside the iPad Air, coming instead in early 2015, with the 12.9-inch iPad Pro to follow in the second quarter of 2015.
While the rumor suggesting the 12.9-inch iPad Pro will be coming in the second quarter of 2015 is in line with previous rumors, there has been no prior indication that second-generation iPad Air and the next-generation Retina iPad mini will see separate launch timelines.
Previous rumors have indicated that both the Retina iPad mini and the iPad Air 2 will be introduced simultaneously at an event in October. Recently, a rumor suggested the two tablets could be introduced at an October 21 media event, but that prediction was quickly shot down by The Loop's Jim Dalrymple. Dalrymple did not, however, rule out an event at another date in October, so an October unveil of the two tablets remains likely. According to recent report from Bloomberg, the iPad Air 2 is in production and the Retina iPad mini 2 is entering production soon.
Both the next-generation iPad Air and Retina iPad mini are expected to gain updated A8 processors, camera improvements, and the Touch ID fingerprint sensor first introduced with the iPhone 5s. Apple's iPad Air 2 may also gain an anti-reflective screen coating and it may also ship in gold, silver, and space gray, much like the iPhone.